Synfacts 2020; 16(10): 1146
DOI: 10.1055/s-0040-1705891
Synthesis of Natural Products and Potential Drugs

Synthesis of (±)-Hibiscone C

Erick M. Carreira
Michael Schneider
Koft ER, Smith III AB. * University of Pennsylvania, Philadelphia, USA
Total Synthesis of Hibiscone C (Gmelofuran).

J. Am. Chem. Soc. 1982;
104: 5568-5570


In 1982, Koft and Smith reported the first total synthesis of (±)-hibiscone C, a ­furanosesquiterpenoid which was isolated from the heart wood of Hibiscus elatus. The synthesis featured the first example of a photochemical intramolecular enone–alkyne cycloaddition.



Alkylation of A with B followed by reductive Stork–Danheiser transposition afforded C. Irradiation of C gave an inconsequential mixture of D and E, which was converted into G via ozonolysis and Paal–Knorr furan synthesis. Allylic oxidation followed by α-methylation yielded (±)-hibiscone C.


Publication History

Publication Date:
17 September 2020 (online)

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